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Segments of Business - Schedule of Segment Information (Details) $ in Millions |  | 3 Months Ended
--- | --- | ---
Apr. 24, 2026 USD ($) | Jun. 30, 2026 USD ($) segment | Jun. 30, 2025 USD ($)
Segment revenues |  |  |
Total revenues |  | $ 105,380 | $ 97,827
Other segment expense, net |  |  |
Total other segment expense, net |  | 103,804 | 96,534
Segment operating profit |  |  |
Subtotal |  | 1,576 | 1,293
Interest expense |  | (77) | (49)
Income before income taxes |  | 1,308 | 1,051
Segment depreciation and amortization |  |  |
Total segment depreciation and amortization |  | 195 | 157
Segment expenditures for long-lived assets |  |  |
Total segment expenditures for long-lived assets |  | $ 152 | 189
Number of reportable segments | segment |  | 4 |
Provision (credit) for bad debts |  | $ 45 | 196
Credits associated with last-in, first-out inventory method |  | (2) | (7)
Restructuring charges |  | 136 | 47
National Prescription Opioid Litigation |  |  |
Segment expenditures for long-lived assets |  |  |
Loss contingency, reduction of accrual | $ 32 |  |
Medical-Surgical Solutions |  |  |
Segment expenditures for long-lived assets |  |  |
Business separation costs |  | 45 |
Operating Segments | North American Pharmaceutical |  |  |
Segment revenues |  |  |
Total revenues |  | 86,773 | 82,729
Other segment expense, net |  |  |
Total other segment expense, net |  | 85,870 | 82,135
Segment operating profit |  |  |
Subtotal |  | 903 | 594
Segment depreciation and amortization |  |  |
Total segment depreciation and amortization |  | 39 | 32
Segment expenditures for long-lived assets |  |  |
Total segment expenditures for long-lived assets |  | $ 64 | $ 61
Revenue derived from services (less than) (as a percent) |  | 1.00% | 1.00%
Provision (credit) for bad debts |  |  | $ 189
Restructuring charges |  | $ 2 | 1
Operating Segments | Oncology & Multispecialty |  |  |
Segment revenues |  |  |
Total revenues |  | 14,222 | 10,658
Other segment expense, net |  |  |
Total other segment expense, net |  | 13,897 | 10,446
Segment operating profit |  |  |
Subtotal |  | 325 | 212
Segment depreciation and amortization |  |  |
Total segment depreciation and amortization |  | 66 | 42
Segment expenditures for long-lived assets |  |  |
Total segment expenditures for long-lived assets |  | $ 18 | $ 24
Revenue derived from services (less than) (as a percent) |  | 7.00% | 7.00%
Operating Segments | Prescription Technology Solutions |  |  |
Segment revenues |  |  |
Total revenues |  | $ 1,566 | $ 1,434
Other segment expense, net |  |  |
Total other segment expense, net |  | 1,340 | 1,181
Segment operating profit |  |  |
Subtotal |  | 226 | 253
Segment depreciation and amortization |  |  |
Total segment depreciation and amortization |  | 19 | 21
Segment expenditures for long-lived assets |  |  |
Total segment expenditures for long-lived assets |  | $ 0 | $ 1
Revenue derived from services (less than) (as a percent) |  | 39.00% | 39.00%
Restructuring charges |  | $ 61 |
Operating Segments | Medical-Surgical Solutions |  |  |
Segment revenues |  |  |
Total revenues |  | 2,819 | $ 2,701
Other segment expense, net |  |  |
Total other segment expense, net |  | 2,697 | 2,480
Segment operating profit |  |  |
Subtotal |  | 122 | 221
Segment depreciation and amortization |  |  |
Total segment depreciation and amortization |  | 26 | 22
Segment expenditures for long-lived assets |  |  |
Total segment expenditures for long-lived assets |  | $ 27 | $ 25
Revenue derived from services (less than) (as a percent) |  | 1.00% | 1.00%
Restructuring charges |  | $ 23 | $ 17
Other |  |  |
Segment revenues |  |  |
Total revenues |  | 0 | 305
Other segment expense, net |  |  |
Total other segment expense, net |  | 0 | 292
Segment operating profit |  |  |
Subtotal |  | 0 | 13
Segment depreciation and amortization |  |  |
Total segment depreciation and amortization |  | 0 | 3
Segment expenditures for long-lived assets |  |  |
Total segment expenditures for long-lived assets |  | 0 | 1
Corporate |  |  |
Segment operating profit |  |  |
Corporate expenses, net |  | (191) | (193)
Segment depreciation and amortization |  |  |
Total segment depreciation and amortization |  | 45 | 37
Segment expenditures for long-lived assets |  |  |
Total segment expenditures for long-lived assets |  | 43 | 77
Restructuring charges |  | 50 | $ 29
Corporate | National Prescription Opioid Litigation |  |  |
Segment expenditures for long-lived assets |  |  |
Loss contingency, reduction of accrual |  | 34 |
Corporate | Medical-Surgical Solutions |  |  |
Segment expenditures for long-lived assets |  |  |
Business separation costs |  | $ 23 |

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